A Model Predictive Control-Based Voltage Optimization Method for Highway Transportation Power Supply Networks With Soft Open Points

Increasing renewable energy penetration exacerbates voltage violation in highway transportation power supply networks (HTPSNs). The technique of flexible connectivity based on soft open points (SOPs) could improve the controllability and voltage stability of the network. However, the generally used voltage control of SOPs may be too sluggish to accommodate the frequent voltage fluctuations and requires further investigation. This article proposes a real-time model predictive control (MPC)-based voltage optimization method for SOPs in HTPSNs. Combining the sensitivity analysis and the operational constraints of the network with SOPs, a localized real-time optimization model is established. With the rolling of the control horizon, the SOPs regulate the voltage and optimize the power flow at a time scale of seconds. Using simply the voltage at the connected node of the SOPs, the proposed method can significantly enhance the voltage stability of the HTPSNs and decrease power losses under the rapid fluctuations of the network voltage. To further improve the performance of voltage control, the optimization model is modified through feedback correction. The case studies demonstrate the effectiveness of the proposed method under different scenarios.